Variability in Perimetry Study (VIPII)
Improved Assessment of Visual Field Change
調査の概要
詳細な説明
Disease of the optic nerve, including glaucoma, is the leading cause of blindness in the United States. Treatment decisions for optic nerve diseases are based largely on the changes in visual function that occur mostly as a consequence of disease progression. Unfortunately, the decision as to whether change of visual function has occurred is often difficult because of the high retest variability of conventional visual field testing (perimetry). This variability is so high that with moderate visual loss, a minimum of six tests are often needed in patients with optic nerve damage to reliably distinguish visual field deterioration from random variation. The preliminary data show that a substantial portion of the variability of perimetry lies in the type of stimulus used and the testing strategy applied.
OBJECTIVES: The investigators propose to test the hypothesis that a large portion of total perimetric variability in patients with visual loss is due to a poor signal-to-noise ratio associated with using a small fixed-size stimulus.
RESEARCH PLAN AND METHODS: To test this hypothesis, the investigators are examining patients with optic nerve diseases with conventional automated perimetry (size III) and tests having large-sized and scaled stimuli (size V, size VI (custom perimeter) and luminance size threshold perimetry - a test where threshold is found by changing stimulus size rather than stimulus intensity). Over four years the investigators will test 100 patients with and glaucoma and 60 normals each eight times. In addition, the investigators are retesting 50 subjects once a week for 5 weeks. The investigators are also studying the associated structural-functional correlations using OCT and developing a statistical model that accounts for correlations of neighboring test locations.
Perimetric variability and the reliable identification of visual field change is the single most difficult problem in visual testing today. The investigators anticipate identifying a method that allows efficient and accurate determination of visual field change. Identification of a superior method would (1) reduce the number of examinations needed, thereby reducing the costs of medical care; (2) minimize misdiagnosis, unnecessary testing and even unnecessary surgery that results from mistakenly interpreting fluctuation of the visual field as progression or improvement; (3) allow earlier disease intervention and (4) reduce the costs of clinical trials.
研究の種類
入学 (実際)
連絡先と場所
研究場所
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Iowa
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Iowa City、Iowa、アメリカ、52246-2208
- Iowa City VA Health Care System, Iowa City, IA
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参加基準
適格基準
就学可能な年齢
健康ボランティアの受け入れ
受講資格のある性別
サンプリング方法
調査対象母集団
説明
Inclusion Criteria:
- Mean deviation of -20 or better with 5-8 points (optimally 10 points) with a value of p= 0.05 or better on the total deviation plot
- Mild cataract with VA of 20/30 or better pinholed
- Refractive error of = to or less than 6 diopters with = or less than 3.50 diopters of cylinder
- Pupil diameter of 3 mm minimum
- Controlled hypertension, diabetes, migraine
- Pseudophakic/refractive surgery if no vision problems
- Trabeculectomy okay
Exclusion Criteria:
- History of other ocular or neurologic disease or surgery
- History of stroke
- Systemic disease [lupus, graves, cancer (within the last 5 yrs), AIDS, other]
- History of amblyopia
- Unreliable patient
- Frequently misses appointments
- Tests poorly
- Ocular hypertension
- Retinal problems
- Diabetic retinopathy
- Neurological disease (IIH, ON, AION)
- Cancer not in remission for the last 5 years
- Vein or artery occlusions
- Macular degeneration
- Trauma with vision loss
- Ocular inflammation (pars planitis, iritis, temporal aeuritis)
研究計画
研究はどのように設計されていますか?
デザインの詳細
- 観測モデル:ケースコントロール
- 時間の展望:見込みのある
コホートと介入
グループ/コホート |
介入・治療 |
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Group 1
glaucoma
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We compared the ability of four perimetric strategies to detect visual field change in the glaucoma arm.
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グループ 2
正常
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We compared the ability of four perimetric strategies to detect visual field change in the glaucoma arm.
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この研究は何を測定していますか?
主要な結果の測定
結果測定 |
メジャーの説明 |
時間枠 |
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Number of Subjects Progressing in Each Group Using Pointwise Linear Regression
時間枠:4 years
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Perimetric method that most efficiently detects visual field change.
secondary outcome: number of subjects progressing in each group using pointwise linear regression Linear regression was used to determine visual field worsening (progression) at each of 52 test locations.
We required 3 or more worsening test locations at a p = 0.05 significance level for their to be significant progression.
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4 years
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協力者と研究者
捜査官
- 主任研究者:Michael Wall, MD、Iowa City VA Health Care System, Iowa City, IA
出版物と役立つリンク
一般刊行物
- Wall M, Doyle CK, Eden T, Zamba KD, Johnson CA. Size threshold perimetry performs as well as conventional automated perimetry with stimulus sizes III, V, and VI for glaucomatous loss. Invest Ophthalmol Vis Sci. 2013 Jun 7;54(6):3975-83. doi: 10.1167/iovs.12-11300.
- Kummet CM, Zamba KD, Doyle CK, Johnson CA, Wall M. Refinement of pointwise linear regression criteria for determining glaucoma progression. Invest Ophthalmol Vis Sci. 2013 Sep 19;54(9):6234-41. doi: 10.1167/iovs.13-11680.
- Wall M, Doyle CK, Zamba KD, Artes P, Johnson CA. The repeatability of mean defect with size III and size V standard automated perimetry. Invest Ophthalmol Vis Sci. 2013 Feb 15;54(2):1345-51. doi: 10.1167/iovs.12-10299.
研究記録日
主要日程の研究
研究開始
一次修了 (実際)
研究の完了 (実際)
試験登録日
最初に提出
QC基準を満たした最初の提出物
最初の投稿 (見積もり)
学習記録の更新
投稿された最後の更新 (実際)
QC基準を満たした最後の更新が送信されました
最終確認日
詳しくは
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